(1) Field of the Invention
This invention relates to a method for preserving the degree of freshness of poultry eggs, such as hen's eggs, quail eggs, and duck eggs.
(2) Description of the Prior Art
When a new-laid poultry shell egg has been stored without washing in a room for a period of from 16 to 42 days, bacteria will be detected in the contents of the egg. However, such a washing is not preferable because washing will destroy a protective cuticula layer on the surface of an egg which is impregnable to most bacteria. As a result, the invasion of bacteria will be in evidence in the contents of the shell egg in about 9 days after washing. Therefore, new-laid poultry shell eggs are usually delivered to retailers' stores the day after laying and displayed for sale on their shelves for at most 3 days. After the term expired, the eggs left unsold are treated to make processed foodstuffs. Judging from the delivery and sanitary point of view, it is worthwhile to prolong the present period of time during which the degree of freshness of eggs is preserved. A present method fop preserving the degree of freshness of eggs comprises coating the surface of a shell egg with mineral oil such as liquid paraffin or an emulsion thereof. The degree of freshness of eggs can be preserved for several months by such a treatment. However, the coating with liquid paraffin is not preferable because such coating induces surface stickiness. Further, there is a safety problem because liquid paraffin is a fraction of mineral oil. Poultry shell eggs are usually pasteurized to sterilize against salmonelas which may be mixed in fecal matters in certain cases. However, said sterilization process does not influence significantly over the preservation of the degree of freshness of eggs.
There is a continuing demand for improvements in the method for preserving the degree of freshness of poultry shell eggs and a composition for the freshness-preservation of poultry shell eggs.